ACPICA: hide private headers
[linux-2.6.git] / drivers / acpi / acpica / tbutils.c
1 /******************************************************************************
2  *
3  * Module Name: tbutils   - table utilities
4  *
5  *****************************************************************************/
6
7 /*
8  * Copyright (C) 2000 - 2008, Intel Corp.
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions, and the following disclaimer,
16  *    without modification.
17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
18  *    substantially similar to the "NO WARRANTY" disclaimer below
19  *    ("Disclaimer") and any redistribution must be conditioned upon
20  *    including a substantially similar Disclaimer requirement for further
21  *    binary redistribution.
22  * 3. Neither the names of the above-listed copyright holders nor the names
23  *    of any contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * Alternatively, this software may be distributed under the terms of the
27  * GNU General Public License ("GPL") version 2 as published by the Free
28  * Software Foundation.
29  *
30  * NO WARRANTY
31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
41  * POSSIBILITY OF SUCH DAMAGES.
42  */
43
44 #include <acpi/acpi.h>
45 #include "accommon.h"
46 #include "actables.h"
47
48 #define _COMPONENT          ACPI_TABLES
49 ACPI_MODULE_NAME("tbutils")
50
51 /* Local prototypes */
52 static acpi_physical_address
53 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size);
54
55 /*******************************************************************************
56  *
57  * FUNCTION:    acpi_tb_check_xsdt
58  *
59  * PARAMETERS:  address                    - Pointer to the XSDT
60  *
61  * RETURN:      status
62  *              AE_OK - XSDT is okay
63  *              AE_NO_MEMORY - can't map XSDT
64  *              AE_INVALID_TABLE_LENGTH - invalid table length
65  *              AE_NULL_ENTRY - XSDT has NULL entry
66  *
67  * DESCRIPTION: validate XSDT
68 ******************************************************************************/
69
70 static acpi_status
71 acpi_tb_check_xsdt(acpi_physical_address address)
72 {
73         struct acpi_table_header *table;
74         u32 length;
75         u64 xsdt_entry_address;
76         u8 *table_entry;
77         u32 table_count;
78         int i;
79
80         table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
81         if (!table)
82                 return AE_NO_MEMORY;
83
84         length = table->length;
85         acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
86         if (length < sizeof(struct acpi_table_header))
87                 return AE_INVALID_TABLE_LENGTH;
88
89         table = acpi_os_map_memory(address, length);
90         if (!table)
91                 return AE_NO_MEMORY;
92
93         /* Calculate the number of tables described in XSDT */
94         table_count =
95                 (u32) ((table->length -
96                 sizeof(struct acpi_table_header)) / sizeof(u64));
97         table_entry =
98                 ACPI_CAST_PTR(u8, table) + sizeof(struct acpi_table_header);
99         for (i = 0; i < table_count; i++) {
100                 ACPI_MOVE_64_TO_64(&xsdt_entry_address, table_entry);
101                 if (!xsdt_entry_address) {
102                         /* XSDT has NULL entry */
103                         break;
104                 }
105                 table_entry += sizeof(u64);
106         }
107         acpi_os_unmap_memory(table, length);
108
109         if (i < table_count)
110                 return AE_NULL_ENTRY;
111         else
112                 return AE_OK;
113 }
114
115 /*******************************************************************************
116  *
117  * FUNCTION:    acpi_tb_initialize_facs
118  *
119  * PARAMETERS:  None
120  *
121  * RETURN:      Status
122  *
123  * DESCRIPTION: Create a permanent mapping for the FADT and save it in a global
124  *              for accessing the Global Lock and Firmware Waking Vector
125  *
126  ******************************************************************************/
127
128 acpi_status acpi_tb_initialize_facs(void)
129 {
130         acpi_status status;
131
132         status = acpi_get_table_by_index(ACPI_TABLE_INDEX_FACS,
133                                          ACPI_CAST_INDIRECT_PTR(struct
134                                                                 acpi_table_header,
135                                                                 &acpi_gbl_FACS));
136         return status;
137 }
138
139 /*******************************************************************************
140  *
141  * FUNCTION:    acpi_tb_tables_loaded
142  *
143  * PARAMETERS:  None
144  *
145  * RETURN:      TRUE if required ACPI tables are loaded
146  *
147  * DESCRIPTION: Determine if the minimum required ACPI tables are present
148  *              (FADT, FACS, DSDT)
149  *
150  ******************************************************************************/
151
152 u8 acpi_tb_tables_loaded(void)
153 {
154
155         if (acpi_gbl_root_table_list.count >= 3) {
156                 return (TRUE);
157         }
158
159         return (FALSE);
160 }
161
162 /*******************************************************************************
163  *
164  * FUNCTION:    acpi_tb_print_table_header
165  *
166  * PARAMETERS:  Address             - Table physical address
167  *              Header              - Table header
168  *
169  * RETURN:      None
170  *
171  * DESCRIPTION: Print an ACPI table header. Special cases for FACS and RSDP.
172  *
173  ******************************************************************************/
174
175 void
176 acpi_tb_print_table_header(acpi_physical_address address,
177                            struct acpi_table_header *header)
178 {
179
180         if (ACPI_COMPARE_NAME(header->signature, ACPI_SIG_FACS)) {
181
182                 /* FACS only has signature and length fields of common table header */
183
184                 ACPI_INFO((AE_INFO, "%4.4s %08lX, %04X",
185                            header->signature, (unsigned long)address,
186                            header->length));
187         } else if (ACPI_COMPARE_NAME(header->signature, ACPI_SIG_RSDP)) {
188
189                 /* RSDP has no common fields */
190
191                 ACPI_INFO((AE_INFO, "RSDP %08lX, %04X (r%d %6.6s)",
192                            (unsigned long)address,
193                            (ACPI_CAST_PTR(struct acpi_table_rsdp, header)->
194                             revision >
195                             0) ? ACPI_CAST_PTR(struct acpi_table_rsdp,
196                                                header)->length : 20,
197                            ACPI_CAST_PTR(struct acpi_table_rsdp,
198                                          header)->revision,
199                            ACPI_CAST_PTR(struct acpi_table_rsdp,
200                                          header)->oem_id));
201         } else {
202                 /* Standard ACPI table with full common header */
203
204                 ACPI_INFO((AE_INFO,
205                            "%4.4s %08lX, %04X (r%d %6.6s %8.8s %8X %4.4s %8X)",
206                            header->signature, (unsigned long)address,
207                            header->length, header->revision, header->oem_id,
208                            header->oem_table_id, header->oem_revision,
209                            header->asl_compiler_id,
210                            header->asl_compiler_revision));
211         }
212 }
213
214 /*******************************************************************************
215  *
216  * FUNCTION:    acpi_tb_validate_checksum
217  *
218  * PARAMETERS:  Table               - ACPI table to verify
219  *              Length              - Length of entire table
220  *
221  * RETURN:      Status
222  *
223  * DESCRIPTION: Verifies that the table checksums to zero. Optionally returns
224  *              exception on bad checksum.
225  *
226  ******************************************************************************/
227
228 acpi_status acpi_tb_verify_checksum(struct acpi_table_header *table, u32 length)
229 {
230         u8 checksum;
231
232         /* Compute the checksum on the table */
233
234         checksum = acpi_tb_checksum(ACPI_CAST_PTR(u8, table), length);
235
236         /* Checksum ok? (should be zero) */
237
238         if (checksum) {
239                 ACPI_WARNING((AE_INFO,
240                               "Incorrect checksum in table [%4.4s] - %2.2X, should be %2.2X",
241                               table->signature, table->checksum,
242                               (u8) (table->checksum - checksum)));
243
244 #if (ACPI_CHECKSUM_ABORT)
245
246                 return (AE_BAD_CHECKSUM);
247 #endif
248         }
249
250         return (AE_OK);
251 }
252
253 /*******************************************************************************
254  *
255  * FUNCTION:    acpi_tb_checksum
256  *
257  * PARAMETERS:  Buffer          - Pointer to memory region to be checked
258  *              Length          - Length of this memory region
259  *
260  * RETURN:      Checksum (u8)
261  *
262  * DESCRIPTION: Calculates circular checksum of memory region.
263  *
264  ******************************************************************************/
265
266 u8 acpi_tb_checksum(u8 *buffer, u32 length)
267 {
268         u8 sum = 0;
269         u8 *end = buffer + length;
270
271         while (buffer < end) {
272                 sum = (u8) (sum + *(buffer++));
273         }
274
275         return sum;
276 }
277
278 /*******************************************************************************
279  *
280  * FUNCTION:    acpi_tb_install_table
281  *
282  * PARAMETERS:  Address                 - Physical address of DSDT or FACS
283  *              Flags                   - Flags
284  *              Signature               - Table signature, NULL if no need to
285  *                                        match
286  *              table_index             - Index into root table array
287  *
288  * RETURN:      None
289  *
290  * DESCRIPTION: Install an ACPI table into the global data structure.
291  *
292  ******************************************************************************/
293
294 void
295 acpi_tb_install_table(acpi_physical_address address,
296                       u8 flags, char *signature, u32 table_index)
297 {
298         struct acpi_table_header *table;
299
300         if (!address) {
301                 ACPI_ERROR((AE_INFO,
302                             "Null physical address for ACPI table [%s]",
303                             signature));
304                 return;
305         }
306
307         /* Map just the table header */
308
309         table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
310         if (!table) {
311                 return;
312         }
313
314         /* If a particular signature is expected, signature must match */
315
316         if (signature && !ACPI_COMPARE_NAME(table->signature, signature)) {
317                 ACPI_ERROR((AE_INFO,
318                             "Invalid signature 0x%X for ACPI table [%s]",
319                             *ACPI_CAST_PTR(u32, table->signature), signature));
320                 goto unmap_and_exit;
321         }
322
323         /* Initialize the table entry */
324
325         acpi_gbl_root_table_list.tables[table_index].address = address;
326         acpi_gbl_root_table_list.tables[table_index].length = table->length;
327         acpi_gbl_root_table_list.tables[table_index].flags = flags;
328
329         ACPI_MOVE_32_TO_32(&
330                            (acpi_gbl_root_table_list.tables[table_index].
331                             signature), table->signature);
332
333         acpi_tb_print_table_header(address, table);
334
335         if (table_index == ACPI_TABLE_INDEX_DSDT) {
336
337                 /* Global integer width is based upon revision of the DSDT */
338
339                 acpi_ut_set_integer_width(table->revision);
340         }
341
342       unmap_and_exit:
343         acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
344 }
345
346 /*******************************************************************************
347  *
348  * FUNCTION:    acpi_tb_get_root_table_entry
349  *
350  * PARAMETERS:  table_entry         - Pointer to the RSDT/XSDT table entry
351  *              table_entry_size    - sizeof 32 or 64 (RSDT or XSDT)
352  *
353  * RETURN:      Physical address extracted from the root table
354  *
355  * DESCRIPTION: Get one root table entry. Handles 32-bit and 64-bit cases on
356  *              both 32-bit and 64-bit platforms
357  *
358  * NOTE:        acpi_physical_address is 32-bit on 32-bit platforms, 64-bit on
359  *              64-bit platforms.
360  *
361  ******************************************************************************/
362
363 static acpi_physical_address
364 acpi_tb_get_root_table_entry(u8 *table_entry, u32 table_entry_size)
365 {
366         u64 address64;
367
368         /*
369          * Get the table physical address (32-bit for RSDT, 64-bit for XSDT):
370          * Note: Addresses are 32-bit aligned (not 64) in both RSDT and XSDT
371          */
372         if (table_entry_size == sizeof(u32)) {
373                 /*
374                  * 32-bit platform, RSDT: Return 32-bit table entry
375                  * 64-bit platform, RSDT: Expand 32-bit to 64-bit and return
376                  */
377                 return ((acpi_physical_address)
378                         (*ACPI_CAST_PTR(u32, table_entry)));
379         } else {
380                 /*
381                  * 32-bit platform, XSDT: Truncate 64-bit to 32-bit and return
382                  * 64-bit platform, XSDT: Move (unaligned) 64-bit to local, return 64-bit
383                  */
384                 ACPI_MOVE_64_TO_64(&address64, table_entry);
385
386 #if ACPI_MACHINE_WIDTH == 32
387                 if (address64 > ACPI_UINT32_MAX) {
388
389                         /* Will truncate 64-bit address to 32 bits, issue warning */
390
391                         ACPI_WARNING((AE_INFO,
392                                       "64-bit Physical Address in XSDT is too large (%8.8X%8.8X), truncating",
393                                       ACPI_FORMAT_UINT64(address64)));
394                 }
395 #endif
396                 return ((acpi_physical_address) (address64));
397         }
398 }
399
400 /*******************************************************************************
401  *
402  * FUNCTION:    acpi_tb_parse_root_table
403  *
404  * PARAMETERS:  Rsdp                    - Pointer to the RSDP
405  *              Flags                   - Flags
406  *
407  * RETURN:      Status
408  *
409  * DESCRIPTION: This function is called to parse the Root System Description
410  *              Table (RSDT or XSDT)
411  *
412  * NOTE:        Tables are mapped (not copied) for efficiency. The FACS must
413  *              be mapped and cannot be copied because it contains the actual
414  *              memory location of the ACPI Global Lock.
415  *
416  ******************************************************************************/
417
418 acpi_status __init
419 acpi_tb_parse_root_table(acpi_physical_address rsdp_address, u8 flags)
420 {
421         struct acpi_table_rsdp *rsdp;
422         u32 table_entry_size;
423         u32 i;
424         u32 table_count;
425         struct acpi_table_header *table;
426         acpi_physical_address address;
427         acpi_physical_address uninitialized_var(rsdt_address);
428         u32 length;
429         u8 *table_entry;
430         acpi_status status;
431
432         ACPI_FUNCTION_TRACE(tb_parse_root_table);
433
434         /*
435          * Map the entire RSDP and extract the address of the RSDT or XSDT
436          */
437         rsdp = acpi_os_map_memory(rsdp_address, sizeof(struct acpi_table_rsdp));
438         if (!rsdp) {
439                 return_ACPI_STATUS(AE_NO_MEMORY);
440         }
441
442         acpi_tb_print_table_header(rsdp_address,
443                                    ACPI_CAST_PTR(struct acpi_table_header,
444                                                  rsdp));
445
446         /* Differentiate between RSDT and XSDT root tables */
447
448         if (rsdp->revision > 1 && rsdp->xsdt_physical_address) {
449                 /*
450                  * Root table is an XSDT (64-bit physical addresses). We must use the
451                  * XSDT if the revision is > 1 and the XSDT pointer is present, as per
452                  * the ACPI specification.
453                  */
454                 address = (acpi_physical_address) rsdp->xsdt_physical_address;
455                 table_entry_size = sizeof(u64);
456                 rsdt_address = (acpi_physical_address)
457                                         rsdp->rsdt_physical_address;
458         } else {
459                 /* Root table is an RSDT (32-bit physical addresses) */
460
461                 address = (acpi_physical_address) rsdp->rsdt_physical_address;
462                 table_entry_size = sizeof(u32);
463         }
464
465         /*
466          * It is not possible to map more than one entry in some environments,
467          * so unmap the RSDP here before mapping other tables
468          */
469         acpi_os_unmap_memory(rsdp, sizeof(struct acpi_table_rsdp));
470
471         if (table_entry_size == sizeof(u64)) {
472                 if (acpi_tb_check_xsdt(address) == AE_NULL_ENTRY) {
473                         /* XSDT has NULL entry, RSDT is used */
474                         address = rsdt_address;
475                         table_entry_size = sizeof(u32);
476                         ACPI_WARNING((AE_INFO, "BIOS XSDT has NULL entry, "
477                                         "using RSDT"));
478                 }
479         }
480         /* Map the RSDT/XSDT table header to get the full table length */
481
482         table = acpi_os_map_memory(address, sizeof(struct acpi_table_header));
483         if (!table) {
484                 return_ACPI_STATUS(AE_NO_MEMORY);
485         }
486
487         acpi_tb_print_table_header(address, table);
488
489         /* Get the length of the full table, verify length and map entire table */
490
491         length = table->length;
492         acpi_os_unmap_memory(table, sizeof(struct acpi_table_header));
493
494         if (length < sizeof(struct acpi_table_header)) {
495                 ACPI_ERROR((AE_INFO, "Invalid length 0x%X in RSDT/XSDT",
496                             length));
497                 return_ACPI_STATUS(AE_INVALID_TABLE_LENGTH);
498         }
499
500         table = acpi_os_map_memory(address, length);
501         if (!table) {
502                 return_ACPI_STATUS(AE_NO_MEMORY);
503         }
504
505         /* Validate the root table checksum */
506
507         status = acpi_tb_verify_checksum(table, length);
508         if (ACPI_FAILURE(status)) {
509                 acpi_os_unmap_memory(table, length);
510                 return_ACPI_STATUS(status);
511         }
512
513         /* Calculate the number of tables described in the root table */
514
515         table_count =
516             (u32) ((table->length -
517                     sizeof(struct acpi_table_header)) / table_entry_size);
518
519         /*
520          * First two entries in the table array are reserved for the DSDT and FACS,
521          * which are not actually present in the RSDT/XSDT - they come from the FADT
522          */
523         table_entry =
524             ACPI_CAST_PTR(u8, table) + sizeof(struct acpi_table_header);
525         acpi_gbl_root_table_list.count = 2;
526
527         /*
528          * Initialize the root table array from the RSDT/XSDT
529          */
530         for (i = 0; i < table_count; i++) {
531                 if (acpi_gbl_root_table_list.count >=
532                     acpi_gbl_root_table_list.size) {
533
534                         /* There is no more room in the root table array, attempt resize */
535
536                         status = acpi_tb_resize_root_table_list();
537                         if (ACPI_FAILURE(status)) {
538                                 ACPI_WARNING((AE_INFO,
539                                               "Truncating %u table entries!",
540                                               (unsigned)
541                                               (acpi_gbl_root_table_list.size -
542                                                acpi_gbl_root_table_list.
543                                                count)));
544                                 break;
545                         }
546                 }
547
548                 /* Get the table physical address (32-bit for RSDT, 64-bit for XSDT) */
549
550                 acpi_gbl_root_table_list.tables[acpi_gbl_root_table_list.count].
551                     address =
552                     acpi_tb_get_root_table_entry(table_entry, table_entry_size);
553
554                 table_entry += table_entry_size;
555                 acpi_gbl_root_table_list.count++;
556         }
557
558         /*
559          * It is not possible to map more than one entry in some environments,
560          * so unmap the root table here before mapping other tables
561          */
562         acpi_os_unmap_memory(table, length);
563
564         /*
565          * Complete the initialization of the root table array by examining
566          * the header of each table
567          */
568         for (i = 2; i < acpi_gbl_root_table_list.count; i++) {
569                 acpi_tb_install_table(acpi_gbl_root_table_list.tables[i].
570                                       address, flags, NULL, i);
571
572                 /* Special case for FADT - get the DSDT and FACS */
573
574                 if (ACPI_COMPARE_NAME
575                     (&acpi_gbl_root_table_list.tables[i].signature,
576                      ACPI_SIG_FADT)) {
577                         acpi_tb_parse_fadt(i, flags);
578                 }
579         }
580
581         return_ACPI_STATUS(AE_OK);
582 }